Jones et al. in WO No. 84/03044 disclose renin inhibiting tetra-, penta-, or hexapeptide analogues of the formula EQU X--D--E--A--B--Z--W
where X and W are terminal groups; D, E, B and Z, of which any one or, except with reduced analogues, two may be absent, are aromatic, lipophilic or (in the case of E) aromatic, lipophilic, or basic amino acid or amino acid analogue residues, and A is an analogue of a lipophilic or aromatic dipeptide residue wherein the peptide link is replaced by one to four-atom carbon or carbon-nitrogen link which as such or in hydrated form is an unhydrolyzable tetrahedral analogue of the transition state of the peptide bond as given above. In particular, A is defined as ##STR2## wherein M can be --CH--OH.
Szelke et al. in European patent application No. 104,041 disclose renin inhibitory polypeptides including the partial sequence EQU X--A--B--Z--W
and EQU X--Phe--His--A--B--Z--W
wherein A is ##STR3## and G is ##STR4## X is hydrogen, protecting group, or an amino acyl residue, B is a lipophilic amino acyl residue, and Z plus W are an amino alcohol residue or Z is aminoacyl and W is hydroxy, ester, amide, etc.
Matsueda et al. in European patent application No. 128,672 disclose renin inhibiting peptides of the formula ##STR5## wherein But represents an isobutyl or sec-butyl group and X includes a group of the formula --CH(R.sup.2)--Y.
Gordon et al. in U.S. Pat. No. 4,514,391 disclose hydroxy substituted peptide compounds of the formula ##STR6## which possess angiotensin converting enzyme or enkephalinase inhibition activity.